1. Machine learning risk prediction of mortality for patients undergoing surgery with perioperative SARS-CoV-2: the COVIDSurg mortality score COVIDSurg Collaborative. The British Journal of Surgery 2021 Nov 11;108(11):1274-1292

2. Effect of COVID-19 pandemic lockdowns on planned cancer surgery for 15 tumour types in 61 countries: international, prospective, cohort study COVIDSurg Collaborative. The Lancet Oncology 2021 Nov;22(11):1507-1517

3. Computer-assisted resection of mandibular cancer and repair with fibula free flap. Case rep I Chatzistefanou, I Tilaveridis, V Banikas, D Deligiannidis, A Saramantos, M Dimakou, P Kouridakis, A Michailidis, G Gkouvas, C Magopoulos. Hellenic Archives of Oral & Maxillofacial Surgery (2021) 2, 109-117

4. Early outcomes and complications following cardiac surgery in patients testing positive for coronavirus disease 2019: An international cohort study Cardiothoracic Interdisciplinary Research Network and COVIDSurg Collaborative. J Thorac Cardiovasc Surg. 2021 Aug; 162(2):e355-e372

5. Head and neck cancer surgery during the COVID-19 pandemic: An international, multicenter, observational cohort study COVIDSurg Collaborative. Cancer 2021 Jul 15;127(14):2476-2488

6. Congenital giant lower eyelid hidrocystoma in a patient with possible orofacial digital syndrome: case report and literature review D Deligiannidis, D Tatsis, D Michailidou, N Pastelli, K Antoniadis. Hellenic Archives of Oral & Maxillofacial Surgery (2021) 1, 5-11

7. Preoperative nasopharyngeal swab testing and postoperative pulmonary complications in patients undergoing elective surgery during the SARS-CoV-2 pandemic COVIDSurg Collaborative. The British Journal of Surgery 2021 Jan 27;108(1):88-96.

8. Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study COVIDSurg Collaborative. Journal of Clinical Oncology 2021 Jan 1;39(1):66-78 3 / 6

9. Myoepithelial carcinoma of minor salivary glands. Report of 2 cases D Deligiannidis, K Paraskevopoulos, N Kechagias, A Ntomouchtsis, K Vahtsevanos. Hellenic Archives of Oral & Maxillofacial Surgery (2020) 3, 135-141

10. Pleomorphic adenoma of lacrimal gland: Surgical management via lateral orbitotomy D Deligiannidis, V Banikas, D Tatsis, C Magopoulos. Hellenic Archives of Oral & Maxillofacial Surgery (2020) 3, 127-133

11. Delaying surgery for patients with a previous SARS-CoV-2 infection COVIDSurg Collaborative. The British Journal of Surgery 2020 Nov;107(12):e601-e602.

12. Metastatic myxoid liposarcoma to the tongue; a unique intraoral metastasis D Tatsis, D Deligiannidis, S Papaemmanouil, K Vahtsevanos. Contemporary Oncology/Współczesna Onkologia (2020) 3, 203-205

13. Tooth within a tooth (dens in dente). A case report and a systematic review of population studies VA Alexoudi, D Tatsis, D Deligiannidis, K Antoniades. Hellenic Archives of Oral & Maxillofacial Surgery (2020) 2, 95-102

14. Diagnostic and therapeutic approach of vascular malformation of the lower lip D Michailidou, D Tatsis, VA Alexoudi, D Deliginannidis, T Grivas,N Pasrelli, K Antoniades. Hellenic Archives of Oral & Maxillofacial Surgery (2020) 2, 85-94

15. Primary osteoclast-like giant cell tumor of parotid gland: Α diagnostic challenge D Deligiannidis, D Tatsis, VA Alexoudi, IS Astreidis, M Kilmpasani, K Vahtsevanos. Hellenic Archives of Oral & Maxillofacial Surgery (2020) 2, 67-75

16. “Jeep Disease” and Optimal Treatment Strategy for Sacrococcygeal Pilonidal Sinus in a High Volume Tertiary Military Medical Center Chatzoulis GA, Pharmakis D, Milias K, Ioannidis K, Tzikos G, Deligiannidis D, Kellidou P, Passos I, Christopoulos C, Moucharisis C, Christodoulou A, Chatzoulis K, Karagiozopoulos T, Spyridopoulos P. Hellenic Journal of Surgery (2019) 91:1, 14-21

  Implant Dentistry, October – November 2024, Online Course by The University of Hong Kong.

Botox, Dermal Fillers & Skin Rejuvenation Training, 27-28 May 2023, FERA Greece, Athens.

Introduction to Nanomedicine, October 2020 – March 2021, Center for Continuing Education and Lifelong Learning, National and Kapodistrian University of Athens.

Practical Training in Microsurgery, September – October 2020 University Clinic of Plastic Surgery AUTH Papageorgiou Hospital, Thessaloniki.

Training in safe and effective transfusion, July 1-2, 2019, Blood Donation Center of G.N.T.H. G. Papanikolaou, Thessaloniki.

Advanced Life Support (A.L.S.), European Resuscitation Council.

Advanced Trauma Life Support (A.T.L.S.), American College of Surgeons.

Basic Life Support (B.L.S.), European Resuscitation Coucil.

1. Member of the European Society of Cranio-Maxillo-Facial Surgery
2. Member of the Greek Society of Oral and Maxillofacial Surgery
3. Member of AOCMF
4. Member of Medical Associations of Lasithi and Heraklion
5. Member of the Dental Association of Lasithi

1.Odontogenic tumors and their management. Deligiannidis D. Conference on Oral Surgery, Stomatological Society of Crete, February 11, 2023, Heraklion

2.Early development of post-radiation fibrosarcoma of the oral cavity. Deligiannidis D., Romanos G., Higumenakis D., Volioti A., Lagoudaki E., Konsolaki E., Head & Neck Cancer Conference,December 16-17, 2022, Athens

3.Metastatic myxoid liposarcoma to the tongue; a rare case report. D. Tatsis, D. Deligiannidis, A. Mantevas, T. Grivas, S. Papaemmanouil, G. Venetis, K. Vahtsevanos, 25th Congress of the European Association for Cranio Maxillo Facial Surgery, 14-16 Ιουλίου 2021

4.Oral field cancerization: a single-center retrospective study. D. Tatsis, D. Deligiannidis, V.A. Alexoudi, K. Paraskevopoulos, K. Antoniades 25th Congress of the European Association for Cranio Maxillo Facial Surgery, 14-16 Ιουλίου 2021

5.Chondroid syringoma of head and neck. A review of the literature. I.S. Astreidis, K. Paraskevopoulos, D. Tatsis, D. Deligiannidis, K. Vaxtsevanos 25th Congress of the European Association for Cranio Maxillo Facial Surgery, 14-16 Ιουλίου 2021

6.Access and Resection of Pleomorphic Adenoma of the Lacrimal Gland via Osteotomy of the Orbit,Deligiannidis D. Banikas B., Magopoulos Ch. 53rd Panhellenic Ophthalmological Congress, October 15-17, 2020, Thessaloniki.

7.Related Hydrocele of the Tear Duct. Deligiannidis D., Tatsis D., Pastelli N., Antoniadis K. 53rd Panhellenic Ophthalmological Conference, Thessaloniki, October 15-17, 2020

8.Field of oral carcinogenesisRetrospective study of the experience of the Clinical Department of Oral and Maxillofacial Surgery of the General Hospital of Thessaloniki ,Tatsis D., Deliayiannidis D., Antoniadis K. 5th Greek Oncology Conference, July 9-11, 2020, Thessaloniki

1The Four Cornerstones of implant success, December 9, 2024, Hellenic Academy of Aesthetic Dentistry

2.Sinus lift made easy, December 5, 2024, ITI Foundation

3.Systematic and local factors in the treatment plan with dental implants, November 20, 2024,Hellenic Prosthetic Company

4.Hot tips for dental implant marketing, October 2, 2024, ITI Foundation

5.An overview of essential updates and techniques in sinus floor elevation, September 4, 2024, ITI Foundation

6.Technological advances in orthognathic surgery,April 4, 2024, European Association for Cranio-Maxillo-Facial Surgery

7.Patient specific orthognathic planning in a cost-conscious healthcare system, March 7, 2024, European Association for Cranio-Maxillo-Facial Surgery

8.HAOMS 2024 – From Analog to Digital Implantology, 31st Panhellenic Conference of the Hellenic Society of Oral and Maxillofacial Surgery, January 26-27 ,Athens.

9.Getting started with bone regeneration: Practical tips,November 28, 2023, ITI Foundation

10.Decision-Making for immediate implants, October 25, 2023, ITI Foundation

11.Endoscopically assisted treatment of condylar fractures, September 21, 2023, European Association for Cranio-Maxillo-Facial Surgery

12.Craniofacial Trauma: The Maxillofacial Perspective, September 14, 2023, European Association for Cranio-Maxillo-Facial Surgery

13.Ballistic Injuries – Principles of Management, March 16, 2023, S.O.R.G. e.V

14SEK Seminar: Topics in Oral & Maxillofacial Surgery for the General Dentist, February 11 2023.

15Head and Neck Cancer Conference, December 16-17, 2022, Athens

16.Guided Flapless Implant Surgery in the Anterior Maxilla: Bone-Grafted vs. Non-Grafted, November 24, 2022, S.O.R.G. e.V

17.Sinus Lifting – (R)evolution of a Concept, September 8, 2022, S.O.R.G. e.V

18.Implantological rehabilitation in head and neck oncology, July 7, 2022 European Association for Cranio-Maxillo-Facial Surgery

19.HAOMS 2022 Guided bone regeneration in implantology, June 3-4, 2022, Athens

20.Osteoradionecrosis: An update,April 7, 2022, European Association for Cranio-Maxillo-Facial Surgery

21.Management of Craniofacial trauma and gunshot wounds,March 17, 2022 European Association for Cranio-Maxillo-Facial Surgery

22.Imaging of the TMJ, February 24 2022, S.O.R.G. e.V

23.TMJ Arthroscopy: From Simple to Complex, February 17 2022, S.O.R.G. e.V

24.Pathophysiology in TMJ Disorders, February 10 2022, S.O.R.G. e.V

25.Controversies in salivary gland surgery, December 2 2021, European Association for Cranio-Maxillo-Facial Surgery

26.Resection of primary tumour-factors beyond margin , November 18 2021, European Association for Cranio-Maxillo-Facial Surgery

27Head and Neck Cancer Conference, November 5-6, 2021, Athens

28.Ablative and Reconstrutive Approaches to Midface Malignancies, October 21 2021, European Association for Cranio-Maxillo-Facial Surgery

29.Management of mandibular fractures, including complex fractures, June 222021, S.O.R.G. e.V

30.Surgical Treatment - Mandibular osteotomies, April 22 2021, S.O.R.G. e.V

31.Surgical Technical Planning - Virtual surgical planning - updated basic concept,April 1 2021, S.O.R.G. e.V

32.Post-extraction implant placement: When immediate, when early and when late.February 28 2021, ITI Foundation

33.HAOMS 2021 Digital Conference, 22-24 January 2021

34.The use of 3D planning in resective and reconstructive Head and Neck surgery, December 11 2020, S.O.R.G. e.V

35.Fibula flap - indications, surgical technique and results December 4 2020, S.O.R.G. e.V

36.Scapula flap - indications, surgical technique and results, November 30 2020, S.O.R.G. e.V

37.Flaps from the femoral condyle – indications, technique and results, November 27 2020, S.O.R.G. e.V

38.Retroauricular vs. preauricular approach - What are the specific benefits, November 26 2020, S.O.R.G. e.V

39.Soft Tissue Flaps (radial, ALT, lat. Dorsi) - Indications, Surgical Technique and Results, November 16 2020, S.O.R.G. e.V

40.Soft tissue reconstruction Indications, Algorithms and Results, November 13 2020, S.O.R.G. e.V

41.Orthognathic Surgical Protocol and Orthodontic Aligners - Do they work together?, November 12 2020, S.O.R.G. e.V

42.Surgical management of the patients with simultaneous TMJ internal derangement ant dentofacial deformity, November 11 2020, S.O.R.G. e.V

43.The Role of Customized Implants in Corrections of Jaw Deformities, November 5 2020, KLS Martin Group

44.TMJ arthroscopic disc repositioning techniques, October 21 2020, S.O.R.G. e.V

45.53rd Pan-Hellenic Ophthalmological Congress, October 15-17, 2020, Thessaloniki

46.Management of the condylar and subcondylar fractures,October 14 2020, S.O.R.G. e.V

47.Contemporary Management of Oral Cancer, October 1 2020, European Association for Cranio-Maxillo-Facial Surgery

48.Post traumatic management of condylar fracture complications and how to avoid them, September 24 2020, S.O.R.G. e.V

49.Best practice to prevent mistakes in orthognathic surgery, September 17 2020, S.O.R.G. e.V

50.Diagnosis and Treatment of Vascular Anomalies, September 15 2020, S.O.R.G. e.V

51.Monthly Oncology Tumor Boards: A Multidisciplinary Approach to Individualized Patient Care - Head and Neck Cancer, August 19 2020, National Comprehensive Cancer Network

52.Individual patient-specific solution in orthognathic surgery, July 23 2020, S.O.R.G. e.V

53.Ballistic Facial Injuries - Early and Secondary Management, July 15 2020, S.O.R.G. e.V

54.The Different Approaches to the TMJ, June 18 2020, S.O.R.G. e.V

55.Outcomes in TMJ Surgery,June 2 2020, Royal College of Surgeons of Edinburgh

1.Conference "Trauma in War and Peace", A' Surgical Clinic 424 G.S.N.E., 16/3/2019, Thessaloniki

2.HAOMS 2024 – From Analog to Digital Implantology, 31stPanhellenic Conference of the Hellenic Society of Oral and Maxillofacial Surgery, January 26-27, Athens.